54 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



the greatest care in this respect, but no doubt many cases of colic, im- 

 paction and constipation are traceable to this source. 



It is not the intent to give the symptoms or prescribe treatment 

 for the diseases arising from an insufficient water supply, but to indi- 

 cate that animals require large quantities of water, and that losses 

 may be expected when not supplied in sufficient quantity or at the 

 proper time. The remedy lies in prevention. 



The losses that arise from an insufficient water supply are small 

 compared with the losses that arise from supplying water of an im- 

 proper character. Whether water will act as an agent for the carry- 

 ing of the germs of disease, the ova, larvae and special stages of para- 

 sites, will depend upon the source from which the water is obtained. 

 If it comes from a deep well that is properly protected, these organ- 

 isms will not be present. If it is obtained from the surface, as small 

 ponds, ditches and streams, they may be present. Not all surface 

 waters are dangerous, but all are more or less exposed to infection 

 and may become dangerous at any time. The time it becomes dan- 

 gerous can not be detected by the eye, and may not be detected by 

 laboratory tests. 



The earth acts as a filter for all germs that fall upon it, no mat- 

 ter what may be their character. Only a small per cent, will pass 

 through the first inch of soil, and a very small number will pass 

 through the first ten feet. In the first few feet of soil most disease 

 germs are destroyed by the forms that inhabit it, but should they 

 pass further down they are restrained only by the mechanical action 

 of the earth. If, however, a soil becomes saturated with germs, as 

 for example in a barn yard, or if the pollution is delivered below the 

 surface, as in a cess-vault, little purification will take place, and the 

 germs may find their way into nearby wells. In order to be certain 

 of the water supply, wells should penetrate an impermeable layer of 

 earth, and the sides be perfectly sealed, as with the iron tubular 

 forms, so that no water can gain entrance except from below. A 

 tubular well twenty feet deep, is a much deeper well, from a sanitary 

 standpoint, than a dug well of the same depth. It is also true that a 

 shallow well may produce pure water at one time and afterwards be- 

 come contaminated because of the saturation of the soil with germs, 

 either by the barnyard or vault. 



Drs. Salmon and Smith came to the conclusion in their investi- 

 gation of hog cholera, that perhaps the most potent agents in the dis- 

 tribution of hog cholera, are streams. They may become infected 

 with the specific germ when sick animals are permitted to go into 

 them, or when dead animals or any part of them are thrown into the 

 water. They may even multiply when the water is contaminated 

 with fecal discharges or other organic matter. Experiments in the 

 laboratory have demonstrated that hog cholera bacilli may remain 

 alive in water for four months. Making all due allowance for ex- 

 ternal influences and competition with the bacteria in natural water, 

 we are forced to assume that they may live at least a month in 

 streams. This would be time enough to inflect every herd along its 



